WO1996009668A1 - Dispositif optique - Google Patents

Dispositif optique Download PDF

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Publication number
WO1996009668A1
WO1996009668A1 PCT/GB1995/002191 GB9502191W WO9609668A1 WO 1996009668 A1 WO1996009668 A1 WO 1996009668A1 GB 9502191 W GB9502191 W GB 9502191W WO 9609668 A1 WO9609668 A1 WO 9609668A1
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Prior art keywords
aαive
waveguide region
output
region
optical
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PCT/GB1995/002191
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English (en)
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WO1996009668B1 (fr
Inventor
David Arthur Owen Davies
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British Telecommunications Public Limited Company
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Publication date
Application filed by British Telecommunications Public Limited Company filed Critical British Telecommunications Public Limited Company
Priority to EP95931340A priority Critical patent/EP0781465B1/fr
Priority to JP51066996A priority patent/JP3895370B2/ja
Priority to US08/809,130 priority patent/US5917972A/en
Priority to CA002199510A priority patent/CA2199510C/fr
Priority to DE69532083T priority patent/DE69532083T2/de
Publication of WO1996009668A1 publication Critical patent/WO1996009668A1/fr
Publication of WO1996009668B1 publication Critical patent/WO1996009668B1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/50—Amplifier structures not provided for in groups H01S5/02 - H01S5/30
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/026—Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S2301/00—Functional characteristics
    • H01S2301/18—Semiconductor lasers with special structural design for influencing the near- or far-field
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/005—Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser pulses, e.g. pulse shaping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/005—Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/0607—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying physical parameters other than the potential of the electrodes, e.g. by an electric or magnetic field, mechanical deformation, pressure, light, temperature
    • H01S5/0608—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying physical parameters other than the potential of the electrodes, e.g. by an electric or magnetic field, mechanical deformation, pressure, light, temperature controlled by light, e.g. optical switch
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/062—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes
    • H01S5/0625—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068—Stabilisation of laser output parameters
    • H01S5/0683—Stabilisation of laser output parameters by monitoring the optical output parameters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/1053—Comprising an active region having a varying composition or cross-section in a specific direction
    • H01S5/1064—Comprising an active region having a varying composition or cross-section in a specific direction varying width along the optical axis
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/50—Amplifier structures not provided for in groups H01S5/02 - H01S5/30
    • H01S5/5054—Amplifier structures not provided for in groups H01S5/02 - H01S5/30 in which the wavelength is transformed by non-linear properties of the active medium, e.g. four wave mixing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/50—Amplifier structures not provided for in groups H01S5/02 - H01S5/30
    • H01S5/509—Wavelength converting amplifier, e.g. signal gating with a second beam using gain saturation

Definitions

  • This invention relates to an optical device and has particular but not exclusive . application to integrated structures formed on a substrate, for use as an amplifier or a modulator.
  • the semicondu ⁇ or material which is used as the a ⁇ ive amplification region of the device suffers from a gain-saturation effe ⁇ which imposes a limitation on 0 the maximum power that can be obtained.
  • proposals have been made in the past to provide the a ⁇ ive amplification region as a tapered structure on the substrate, which widens along its length so that as amplification proceeds, a greater cross se ⁇ ion of material is available for amplification, permitting increased amplification s power to be achieved.
  • an optical device comprising an elongate waveguide having a boundary that extends along the length thereof to an optical output at one end, and an a ⁇ ive material for producing amplification of light travelling in the waveguide, the waveguide boundary being configured to concentrate the amplified light laterally within the waveguide towards the output.
  • the light can be concentrated within the waveguide region itself, towards the output, without the need for additional lens stru ⁇ ures.
  • the waveguide region may have a width which tapers along the length thereof towards the output to achieve the concentration of the amplified light.
  • Optical amplification can be achieved by applying an ele ⁇ ric current to the a ⁇ ive material, and the current density that in use passes through the active material may be imparted with a non-uniform spatial profile in order to avoid optical gain saturation.
  • the ele ⁇ ric current may be fed into the active material through a co ⁇ du ⁇ ive layer configured in first and second separate s portions so that different values of current can be fed to different regions of the a ⁇ ive material.
  • gain saturation may be used advantageously in the device to achieve modulation for 0 data transmission purposes.
  • the device may have a first source of optical data pulses coupled to an input to the waveguide region and a second source of optical radiation e.g. essentially continuous radiation, coupled to the waveguide region.
  • the data pulses from the first source and the radiation from the second source intera ⁇ so as to s produce a gain saturation in the a ⁇ ive material, so that the radiation from the second source is amplitude modulated by the data pulses.
  • a filter may be provided to pass preferentially the resulting pulse modulated signal.
  • the sources may intera ⁇ so that the radiation from the second source is phase modulated by the data pulses from the first source at a relevant receiver, and a 0 phase dete ⁇ or may be used to dete ⁇ the modulation.
  • the radiation from the two sources may intera ⁇ to produce radiation at the output which is of a different wavelength from the pumping radiation and the data pulses. This output radiation may be a phase conjugate of the radiation from the first source.
  • the a ⁇ ive material may extend over the entire extent of the waveguide region, or for a high power amplifier, the waveguide region may include a first a ⁇ ive portion coupled to the a ⁇ ive material, and a second passive portion with its boundary configured to concentrate the amplified light, 0 thereby avoiding gain saturation.
  • Refle ⁇ ive means may be provided at opposite ends of the a ⁇ ive region in order to induce a laser a ⁇ ion therein.
  • the device may be fabricated on a substrate, with the waveguide region comprising a buried heterostructure.
  • the waveguide region may s comprise a rib waveguide structure.
  • Figure 1 is a plan view of an a ⁇ ive amplification region for a device in accordance with the invention
  • Figure 2 is a schematic se ⁇ ional view of the device shown in Figure 1 when is fabricated according to a first embodiment
  • Figure 3 is a schematic se ⁇ ional view of a substrate with epitaxial layers used for forming the device as shown in Figure 2;
  • Figure 4 is a schematic se ⁇ ion of the device of Figure 1 when fabricated according to a second embodiment of the invention
  • Figure 5 is a schematic diagram of a device in accordance with the invention, which uses gain saturation and/or a wavelength conversion in order to achieve data modulation;
  • Figure 6 illustrates a version of the device which uses a phase shift in its output to achieve phase modulated data pulses
  • Figure 7 is a plan view of another optical device in accordance with the invention.
  • Figure 8 is a schematic se ⁇ ional view of the device shown in Figure 7 taken along the line B-B', when fabricated according to a first procedure;
  • Figure 9 is a corresponding se ⁇ ional view of a device shown in Figure 7, 0 when fabricated according to a second procedure. Detailed Description
  • Figure 1 illustrates in plan view a semicondu ⁇ or optical device A in accordance with the present invention which, in the described embodiments is fabricated in the InGaAsP material system for use in telecommunication systems with wavelengths centred on 1.3 and 1.55 ⁇ m.
  • the device consists of an elongate waveguide region 1 which produces a ⁇ ive amplification, formed on a substrate 2.
  • the elongate waveguide region 1 has an input 3 at one end for optical radiation and an optical output 4 at its other, second end.
  • the input and output 3, 4 are configured to couple onto single mode optical waveguides e.g. optical fibres or alternatively other stru ⁇ ures (not shown) integrated onto the substrate.
  • the width w of the waveguide region 1 increases progressively from the input 3 in the dire ⁇ ion of the length / of the waveguide towards the central or intermediate region 5, from which the width w progressively decreases to the output 4.
  • a typical example of the device has a length / of 500 ⁇ m - 1 mm, with the inputs 3 and 4 having a width w of 1 - 2 ⁇ m, and the width w in the intermediate region being of the order of 30 - 40 ⁇ m.
  • the waveguide region 1 can be fabricated in a number of different ways and two examples will now be described with reference to Figures 2 to 4.
  • FIG 2 shows a schematic cross se ⁇ ion taken along the line A-A' of Figure 1 for which the waveguide region 1 is fabricated as a buried heterostru ⁇ ure.
  • the waveguide region 1 comprises a layer of a ⁇ ive i-InGaAsP material 6 formed on a n-InP layer 7, itself formed on a n-InP substrate 8.
  • the a ⁇ ive material 6 is overlaid by a p-InP region 9 formed with a condu ⁇ ive over-conta ⁇ 10 of p-InGaAsP material.
  • the general stru ⁇ ure of the amplifier, the thicknesses of the various layers and the dopant concentrations, are conventional and reference is dire ⁇ ed to A.W. Nelson, W. J. Devlin, R. E. Hobbs, C.G.D. Le on and S. Wong: "High-power, low- threshold BH lasers operating at 1.52 ⁇ m grown entirely by MOVPE", Ele ⁇ ronics Letters, Vol. 21, No. 20, pp 888-889 (26 September 1985).
  • the stru ⁇ ure is formed from an initial substrate 8 which is formed with layers 6, 7, 9 and 10 over its entire surface in a manner known per se, and material is then sele ⁇ ively etched from the regions shown in dotted outline, using a mask in a manner known per se, the mask having a shape as shown in Figure 1, so as to define the varying width w of the waveguide region along the length thereof.
  • p-InP layer 11 and n-InP layer 12 are formed overlying the sele ⁇ ively etched regions by standard MOVPE ele ⁇ ric growth techniques.
  • An ele ⁇ rically condu ⁇ ive bottom metallisation layer 13 is formed on the underside of the substrate.
  • the a ⁇ ive material 6 is sandwiched between p-InP region 9 and n-InP layer 7 so that when a voltage is applied between the condu ⁇ ive layer 10 and the bottom layer 13, an ele ⁇ ric current passes through the a ⁇ ive material 6.
  • the polarity of the voltage and the arrangement of the n and p doped layers 11 and 12 is such that in use, they form a reverse-biased jun ⁇ ion, with the result that the current is dire ⁇ ed sele ⁇ ively through the waveguide region 1 rather than to each side.
  • photons incident on input 3 Figure 1 cause ele ⁇ rons to traverse the band gap of the a ⁇ ive material 6 so as to generate additional photons, thereby producing optical amplification in the waveguide region.
  • the waveguide region has its boundary defined by means of a rib waveguide.
  • the device consists of a substrate 14, formed of n-InP material with an overlayer 15 of optically a ⁇ ive i-InGaAsP material in a waveguide region 1 shown in dotted outline.
  • the layer 15 is overlaid by an etch-stop layer 16 of p-InGaAsP material which is overlaid by a rib 9 of p-InP material, itself covered by a condu ⁇ ive conta ⁇ region 10 of p-InGaAsP material.
  • the layers 9 and 10 are formed in the curved shape shown in Figure 1 by a lithographic mask and sele ⁇ ive etching in a similar manner to that described with reference to Figure 2.
  • the resulting stru ⁇ ure is overlaid with a diele ⁇ ric material 17, typically silicon dioxide.
  • a voltage is applied to the layer 10
  • a current is established through the region of layer 15 which is overlaid by the layer 9, so that amplification occurs therein within the region 1 shown in dotted outline. It will be appreciated that the optical confinement produced by the structure shown in Figure 4 is less well defined than with the configuration of Figure 2.
  • the single mode optical signal applied to input 3 is thus amplified within the waveguide region 1.
  • the single mode expands adiabatically towards the central, intermediate region 5, and is thereafter adiabatically contra ⁇ ed, still in the single mode, and inserted through the output 4 e.g. into an output optical fibre conne ⁇ ed thereto (not shown).
  • adiabatic we mean no significant coupling into higher order transmission modes.
  • the boundaries of waveguide region 1 themselves a ⁇ to concentrate the amplified light laterally to the output 4, with the advantage that no additional lens stru ⁇ ures are required to focus the amplified light into the output optical fibre, as in the prior art .
  • the condu ⁇ ive layer 10 is arranged in two portions 10a, 10b that overlie corresponding regions la, lb of the waveguide region 1.
  • the current densities in the regions 10a and 10b are sele ⁇ ed individually so as to be higher in region 10a than in region 10b, such that amplification primarily occurs in the a ⁇ ive material 6 in the region la, where the outwardly tapered shape of the region reduces the risk of gain saturation .
  • the waveguide region 1 a ⁇ s to concentrate the resulting amplified light into the output 4 without further significant amplification in the underlying a ⁇ ive material 6, so as to minimise the risk of gain saturation.
  • the region 10a in this example is fed with a higher current than the region 10b in order to achieve the desired current density differential.
  • the condu ⁇ ive layer 10 could be arranged in more than two portions so as to profile the current density spatially through the a ⁇ ive material 6 and thereby minimise optical gain saturation.
  • the refle ⁇ ivity needs to be sufficiently low to avoid laser a ⁇ ion even at high drive currents, i.e. refle ⁇ ivity of the order of 0.001 or, preferably, 0.0001.
  • refle ⁇ ivity of the order of 0.001 or, preferably, 0.0001.
  • one or more of the facets 18, 19 may be left uncoated or one end may be high-refle ⁇ ive coated, so as to produce semi-refle ⁇ ive end regions that promote resonance within the region.
  • the uncoated refle ⁇ ivity is normally around 0.3, and a high-refle ⁇ ivity coating would produce refle ⁇ ivities of around 0.9 or higher.
  • the device A of Figure 1 is shown with an optical fibre 20 conne ⁇ ed to its input, the fibre including a coupler 21 which has a first input port 22 that receives a stream of optical data pulses at a wavelength ⁇ , and a ⁇ s as a first source for the device, and a second input port 23 that receives essentially continuous wave (cw) radiation at a second different wavelength ⁇ 2> the second port 23 a ⁇ ing as a second source for the device A.
  • the wavelengths ⁇ dress ⁇ 2 are chosen to be within the gain bandwidth of the a ⁇ ive material 6 in the waveguide region 1.
  • both of the regions 10a,10b are fed with a bias voltage that results in an optical amplification, and the level of amplification in region lb ( Figure 1), in the absence of ⁇ , is close to, but does not exceed the level at which gain-saturation occurs.
  • the device A according to the invention has the significant advantage that the waveguide region la produces sufficient amplification of the data pulse stream ⁇ , and the cross modulation can then occur in region lb, in an integrated device, thereby providing a very compa ⁇ and efficient means for producing switching using gain saturation, for use as a modulator. Also, the speed of the cross modulation effe ⁇ is enhanced by the concentration of light produced in the region lb, in comparison to a conventional amplifier with an untapered waveguide.
  • the output from the device A in Figure 5 is fed through an optical fibre 24 to a bandpass filter 25 tuned to the radiation wavelength ⁇ ; in order to separate the amplified output signal.
  • the device A according to the invention can also be used as in Figure 6 to exploit another non-linear effe ⁇ . As described in B. Mikkelsen et al, supra an input at wavelength ⁇ , can be used to phase shift radiation at a different wavelength ⁇ ; . This effe ⁇ is exploited in the configuration shown in Figure 6 to achieve phase modulation.
  • the input data pulses ⁇ , and the cw radiation ⁇ 2 are applied through coupler 26 to the input 3 of the device A through coupler 21, as previously described with reference to Figure 5 and additionally, the cw radiation is fed through the coupler 26 and a variable amplifier or attenuator 27 to be mixed with the output of the device A through a coupler 28.
  • the cw radiation ⁇ 2 is phase modulated in the device A by the data pulses ⁇ ,.
  • the resulting phase modulation produced at the output of device A is compared, by means of the coupler 28, with the phase of the cw radiation ⁇ 2 , which a ⁇ s as a reference, with the result that the output in fibre 24 is amplitude modulated in accordance with the phase modulation that occurs in device A.
  • the third wavelength signal ⁇ 3 may be a phase conjugate of the cw radiation ⁇ 2 as described in M.C. Tatham et al, "Compensation of fibre Chromatic Dispersion by Optical Phase Conjugation in a Semicondu ⁇ or Laser Amplifier", El Lett., 29 pp 1851-2, 1993.
  • the specific shape adopted for the waveguide region 1 varies from application to application.
  • a symmetrical configuration as shown in Figure 1 is advantageous, with the locus of the boundary of the region 1 conforming to portions of circles, in regions x, y, z close to the inputs and outputs, and in the intermediate region 5.
  • the conne ⁇ ing regions of the boundary, in regions p conform to portions of a parabola.
  • Many other modifications and variations will be readily s apparent and the rate of increase and decrease of the width w in the waveguide region can vary along the length thereof depending upon the particular application and non-linear effe ⁇ that is to be exploited.
  • the output 4 of the device may include o a further non-tapered elongate region (not shown) formed integrally on the substrate, which may include a continuation of the layer 6 of optically a ⁇ ive material.
  • the a ⁇ ive material 6 which produces optical amplification, extends over the entire extent of the optical waveguide region 1.
  • the a ⁇ ive material 6 is disposed solely in a first a ⁇ ive portion 30 of the waveguide region 1, and the remaining part of the waveguide 1 constitutes a second, passive portion 31, which is transparent for the relevant wavelength range of light travelling in the waveguide.
  • the device can be used advantageously as a high power amplifier, with the passive portion 31 providing an integrated stru ⁇ ure for dire ⁇ ing the amplified light into the output 4 e.g. to an optical waveguide, without the problem of gain saturation.
  • the a ⁇ ive and passive portions 30, 31 of the waveguide can be formed in a number of different ways. Referring now to Figure 8, this shows a se ⁇ ion taken along B-B' of Figure 7 according to a first stru ⁇ ure.
  • the general stru ⁇ ure is similar to that shown in Figure 2.
  • the waveguide region 1 is defined by an additional layer 32 of InGaAsP material, which has a bandgap sele ⁇ ed so that it is transparent to the amplified optical radiation and is hence passive.
  • the optically a ⁇ ive material is provided as the layer 6 which, as previously described, is formed of i-InGaAsP material, but in this embodiment, overlies the layer 32 solely in the a ⁇ ive portion 30.
  • the layer 6 thus produces amplification of light travelling in the waveguide.
  • the layer 6 is sandwiched between a p-InP layer 9 and a n-InP layer 7, with a condu ⁇ ive over-conta ⁇ 10 of p-InGaAsP material.
  • the layers 32, 6, 9 and 10 are formed as continuous layers over the entire surface area and then the layers 6, 9 and 10 are sele ⁇ ively etched from the passive portion, and replaced by a cladding region 33 of i-InP material, which is grown in its place. The resulting configuration is then sele ⁇ ively masked and etched to provide the curved waveguide boundary, as described with reference to Figures 1 and 2.
  • the a ⁇ ive layer 6 was formed 0.15 ⁇ m thick with a bandgap of about 1.55 ⁇ m and the layer 32 had a thickness of 0.4 ⁇ m and a bandgap of 1.1 ⁇ m.
  • the waveguide may be formed as a ridge stru ⁇ ure, by forming the layer 32 as a continuous layer, and forming a ridge from the layers 6, 9, 10 and 33 according to general techniques disclosed in Sherlock, G., Burton, J., Fiddyment, P., Sully, P., Kelly, A., and Robertson M. "An Integrated 2x2 Optical Switch with Gain", Ele ⁇ ronics Letters 30 (1994), pp 137-8.
  • the passive layer 32 is omitted.
  • the layers 6, 9 and 10 are sele ⁇ ively etched and then a passive layer 34 of InGaAsP is grown so as to form a continuation of the layer 6, as a heterolayer.
  • the layer 34 typically chosen to have a bandgap of 1.3 ⁇ m when the device is to operate at 1.5 ⁇ m.
  • the layer 34 can o be grown by metal-organic vapour phase epitaxy (MOVPE). By this technique, the layers 6 and 34 can be formed with an optical quality waveguide jun ⁇ ion at which no significant refle ⁇ ion occurs.
  • the layer 34 is then covered by a cladding region 35 of p-InP material.
  • the resulting stru ⁇ ure is then sele ⁇ ively masked and etched to provide the curved s waveguide boundary, as previously described.
  • MOVPE can be found in "1.55 ⁇ m Butt-jointed Distributed Bragg Refle ⁇ or Lasers Grown Entirely by Low-pressure MOVPE", Y. Tohmori and M. Oishi, Jap. J. App. Phys. 27 (1988), pp. L693-695.
  • the embodiments shown in Figure 7 to 9 have the advantage that amplification can occur in the a ⁇ ive portion without significant gain saturation, due to the increasing width of the a ⁇ ive portion 30 along the length of the device and that, the resulting amplified light can then be concentrated within the waveguide region 1 by the S a ⁇ ion of its boundary, so as to be dire ⁇ ed to the output 4 without problems of saturation effe ⁇ s due to gain saturation, as a result of the passive nature of portion 31 of the waveguide, and without the need for additional separate lens stru ⁇ ures.
  • optical radiation includes visible and non-visible radiation such as ultra-violet and infra-red.

Abstract

L'invention concerne un dispositif optique conçu pour être utilisé comme amplificateur ou modulateur. Ce dispositif comprend un substrat à semiconducteurs (2) pourvu d'une zone allongée formant guide d'ondes (1) et présentant une frontière de guidage de la lumière et s'étend entre une entrée (3) et une sortie (4) pour assurer un rayonnement optique. Une couche optiquement active d'un matériau (6) assure l'amplification de la lumière traversant la zone formant guide d'ondes (1). La largeur (w) de la zone (1) est réduite vers l'extérieur à partir de l'entrée pour permettre l'amplification des signaux optiques d'entrée, et est réduite vers la sortie (4) de manière à concentrer la lumière amplifiée en un seul mode vers la sortie. La concentration de la lumière amplifiée dans la zone active peut générer des effets non linéaires qui sont exploités pour assurer une modulation de données ou une commutation. Dans un mode de réalisation, la zone formant guide d'ondes comprend une première zone active (30) pour amplifier la lumière et une deuxième zone passive (31) pour concentrer la lumière vers la sortie.
PCT/GB1995/002191 1994-09-14 1995-09-14 Dispositif optique WO1996009668A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
EP95931340A EP0781465B1 (fr) 1994-09-14 1995-09-14 Dispositif optique
JP51066996A JP3895370B2 (ja) 1994-09-14 1995-09-14 光デバイス
US08/809,130 US5917972A (en) 1994-09-14 1995-09-14 Optical device
CA002199510A CA2199510C (fr) 1994-09-14 1995-09-14 Dispositif optique
DE69532083T DE69532083T2 (de) 1994-09-14 1995-09-14 Optische vorrichtung

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP94306753 1994-09-14
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GBGB9425729.2A GB9425729D0 (en) 1994-09-14 1994-12-20 Otical device
GB9425729.2 1994-12-20

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WO1996009668B1 WO1996009668B1 (fr) 1996-05-23

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0864886A1 (fr) * 1997-03-13 1998-09-16 Alcatel Procédé de fabrication de circuits optiques intégrés permettant de minimiser les pertes optiques de couplage
EP0898348A1 (fr) * 1997-08-18 1999-02-24 Nec Corporation Amplificateur optique à semi-conducteur
EP0908959A2 (fr) * 1997-10-07 1999-04-14 Sarnoff Corporation Diode à semi-conducteur
EP0915543A1 (fr) * 1997-11-10 1999-05-12 Alcatel Amplificateur optique semi-conducteur et source laser intégrée l'incorporant
FR2779838A1 (fr) * 1998-06-15 1999-12-17 Alsthom Cge Alcatel Composant optique a semiconducteur et amplificateur et convertisseur de longueurs d'onde constitues par ce composant
WO2000068720A1 (fr) * 1999-05-06 2000-11-16 Sarnoff Corporation Structure de conjugaison de phase pour adaptation de mode dans un amplificateur optique
US10758886B2 (en) 2015-09-14 2020-09-01 Arizona Board Of Regents On Behalf Of Arizona State University Conditioned surfaces for in situ molecular array synthesis
US11371990B2 (en) 2016-11-11 2022-06-28 Cowper Sciences Inc. Methods for identifying candidate biomarkers
US11747334B2 (en) 2016-06-20 2023-09-05 Cowper Sciences Inc. Methods for differential diagnosis of autoimmune diseases
US11774446B2 (en) 2016-06-20 2023-10-03 Cowper Sciences Inc. Methods for diagnosis and treatment of autoimmune diseases

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2768524B1 (fr) * 1997-09-12 1999-10-22 France Telecom Amplificateur a large surface avec recombineur a interferences multimodes
JP3045115B2 (ja) * 1997-09-30 2000-05-29 日本電気株式会社 光半導体装置の製造方法
US6819687B1 (en) * 1997-12-10 2004-11-16 Nellcor Puritan Bennett Incorporated Non-imaging optical corner turner
FR2786278B1 (fr) * 1998-11-24 2001-01-26 Cit Alcatel Composant optique a semi-conducteur comportant un adapteur de mode
SE9902916L (sv) * 1999-08-16 2001-02-17 Ericsson Telefon Ab L M Modulator och integrerad krets
DE60106742T2 (de) * 2000-02-25 2005-03-10 Trumpf Photonics, Inc. Hochleistungs-superleuchtdiode mit einem gekrümmten mehrfachdurchgangs-wellenleiter
SE521023C2 (sv) * 2000-07-07 2003-09-23 Ericsson Telefon Ab L M Optisk anordning samt framställning därav
IES20000820A2 (en) * 2000-10-11 2002-05-29 Nat Univ Ireland A single frequency laser
US20020176152A1 (en) * 2001-05-04 2002-11-28 Paola Parolari Intensity modulation of optical signals
KR100393193B1 (ko) * 2001-09-29 2003-07-31 삼성전자주식회사 광 도파로와 ｍｅｍｓ 액추에이터를 구비한 가변 광 감쇠기
KR100446524B1 (ko) * 2002-11-25 2004-09-04 삼성전자주식회사 파장분할 다중화/역다중화기
EP1624325B1 (fr) * 2004-08-03 2013-05-22 STMicroelectronics Srl Structure optique intégrée, sensible à l'énergie rayonnée dans la gaine d'un circuit optique planaire
JP4505470B2 (ja) * 2005-01-20 2010-07-21 富士通株式会社 光導波路デバイス及び半導体デバイス
US8615029B2 (en) * 2009-12-30 2013-12-24 Ipg Photonics Corporation Optical device
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JP6245419B1 (ja) * 2017-04-04 2017-12-13 三菱電機株式会社 半導体装置、半導体装置の製造方法
WO2023049297A1 (fr) * 2021-09-23 2023-03-30 Freedom Photonics Llc Contact segmenté pour commande de courant dans des lasers à semi-conducteur et amplificateurs optiques

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5850790A (ja) * 1981-09-19 1983-03-25 Mitsubishi Electric Corp 光半導体デバイス
EP0135594A1 (fr) * 1983-02-22 1985-04-03 Sony Corporation Laser a semiconducteur
US4815084A (en) * 1987-05-20 1989-03-21 Spectra Diode Laboratories, Inc. Semiconductor laser with integrated optical elements
JPH03284892A (ja) * 1990-03-30 1991-12-16 Fujitsu Ltd 光増幅装置
US5179568A (en) * 1991-08-28 1993-01-12 The United States Of America As Represented By The United States National Aeronautics And Space Administration Self-collimated unstable resonator semiconductor laser
US5202948A (en) * 1990-11-08 1993-04-13 Kabushiki Kaisha Toshiba Traveling-wave type light amplifier
EP0632299A2 (fr) * 1993-07-03 1995-01-04 Robert Bosch Gmbh Elément optoélectrique avec réseau de réaction

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2598862B1 (fr) * 1986-05-16 1994-04-08 Bouley Jean Claude Laser a semi-conducteur a reaction distribuee et a longueur d'onde continument accordable.
US5140651A (en) * 1991-06-27 1992-08-18 The United States Of America As Represented By The Secretary Of The Air Force Semiconductive guided-wave programmable optical delay lines using electrooptic fabry-perot elements
US5392308A (en) * 1993-01-07 1995-02-21 Sdl, Inc. Semiconductor laser with integral spatial mode filter
FR2709566B1 (fr) * 1993-09-02 1995-09-29 Alcatel Nv Composant optique actif semiconducteur à ruban.
US5517517A (en) * 1994-06-30 1996-05-14 At&T Corp. Semiconductor laser having integrated waveguiding lens
US7268113B2 (en) * 2001-02-02 2007-09-11 Conjuchem Biotechnologies Inc. Long lasting growth hormone releasing factor derivatives

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5850790A (ja) * 1981-09-19 1983-03-25 Mitsubishi Electric Corp 光半導体デバイス
EP0135594A1 (fr) * 1983-02-22 1985-04-03 Sony Corporation Laser a semiconducteur
US4815084A (en) * 1987-05-20 1989-03-21 Spectra Diode Laboratories, Inc. Semiconductor laser with integrated optical elements
JPH03284892A (ja) * 1990-03-30 1991-12-16 Fujitsu Ltd 光増幅装置
US5202948A (en) * 1990-11-08 1993-04-13 Kabushiki Kaisha Toshiba Traveling-wave type light amplifier
US5179568A (en) * 1991-08-28 1993-01-12 The United States Of America As Represented By The United States National Aeronautics And Space Administration Self-collimated unstable resonator semiconductor laser
EP0632299A2 (fr) * 1993-07-03 1995-01-04 Robert Bosch Gmbh Elément optoélectrique avec réseau de réaction

Non-Patent Citations (7)

* Cited by examiner, † Cited by third party
Title
KOYAMA F ET AL: "MULTI-QUANTUM-WELL GAINAS/GAINASP TAPERED BROAD-AREA AMPLIFIERS WITH MONOLITHICALLY INTEGRATED WAVEGUIDE LENS FOR HIGH-POWER APPLICATIONS", IEEE PHOTONICS TECHNOLOGY LETTERS, vol. 5, no. 8, 1 August 1993 (1993-08-01), pages 916 - 919, XP000399645 *
P. DOUSSIERE ET AL: "Clamped gain travelling wave semiconductor optical amplifier for wavelength division multiplexing applications", PROCEEDINGS OF THE 14TH IEEE INTERNATIONAL SEMICONDUCTOR LASER CONFERENCE, SEPTEMBER 19-23 1994 MAUI, HAWAI, USA, PAPER W2.1, pages 185 - 186, XP000514864 *
P. SPANO ET AL: "Frequency conversion in semiconductor lasers and amplifiers", EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS AND RELATED TECHNOLOGIES, vol. 5, no. 4, MILANO IT, pages 103 - 113, XP000460566 *
PATENT ABSTRACTS OF JAPAN vol. 007, no. 136 (E - 181) 14 June 1983 (1983-06-14) *
PATENT ABSTRACTS OF JAPAN vol. 016, no. 112 (E - 1180) 19 March 1992 (1992-03-19) *
STUBKJAER K E ET AL: "RECENT ADVANCES IN SEMICONDUCTOR OPTICAL AMPLIFIERS AND THEIR APPLICATIONS", PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE AND RELATED MATERIALS, NEWPORT, APR. 21 - 24, 1992, no. CONF. 4, 21 April 1992 (1992-04-21), INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, pages 242 - 245, XP000341267 *
STUBKJAER K ET AL: "SEMICONDUCTOR OPTIAL AMPLIFIERS AS LINEAR AMPLIFIERS, GATES AND WAVELENGTH CONVERTERS", PROCEEDINGS OF THE EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION (EC, MONTREUX, SEPT. 12 - 16, 1993 INVITED PAPERS, vol. 1, 12 September 1993 (1993-09-12), SWISS ELECTROTECHNICAL ASSOCIATION, pages 60 - 67, XP000492152 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0864886A1 (fr) * 1997-03-13 1998-09-16 Alcatel Procédé de fabrication de circuits optiques intégrés permettant de minimiser les pertes optiques de couplage
FR2760850A1 (fr) * 1997-03-13 1998-09-18 Alsthom Cge Alcatel Procede de fabrication de circuits optiques integres permettant de minimiser les pertes optiques de couplage
US6160927A (en) * 1997-03-13 2000-12-12 Alcatel Method of fabricating integrated optical circuits which minimizes optical coupling losses
EP0898348A1 (fr) * 1997-08-18 1999-02-24 Nec Corporation Amplificateur optique à semi-conducteur
US6148132A (en) * 1997-08-18 2000-11-14 Nec Corporation Semiconductor optical amplifier
EP0908959A3 (fr) * 1997-10-07 2000-05-24 Sarnoff Corporation Diode à semi-conducteur
EP0908959A2 (fr) * 1997-10-07 1999-04-14 Sarnoff Corporation Diode à semi-conducteur
US6137625A (en) * 1997-11-10 2000-10-24 Alcatel Semiconductor optical amplifier and integrated laser source information
FR2770938A1 (fr) * 1997-11-10 1999-05-14 Alsthom Cge Alcatel Amplificateur optique semi-conducteur et source laser integree l'incorporant
EP0915543A1 (fr) * 1997-11-10 1999-05-12 Alcatel Amplificateur optique semi-conducteur et source laser intégrée l'incorporant
FR2779838A1 (fr) * 1998-06-15 1999-12-17 Alsthom Cge Alcatel Composant optique a semiconducteur et amplificateur et convertisseur de longueurs d'onde constitues par ce composant
EP0966078A1 (fr) * 1998-06-15 1999-12-22 Alcatel Composant optique à semiconducteur et amplificateur et convertisseur de longueurs d'onde constitués par ce composant
WO2000068720A1 (fr) * 1999-05-06 2000-11-16 Sarnoff Corporation Structure de conjugaison de phase pour adaptation de mode dans un amplificateur optique
US6614585B1 (en) 1999-05-06 2003-09-02 Trumpf Photonics Inc. Phase conjugating structure for mode matching in super luminescent diode cavities
US6754001B2 (en) 1999-05-06 2004-06-22 Trumpf Photonics Inc. Phase conjugating structure for mode matching in super luminescent diode cavities
US10758886B2 (en) 2015-09-14 2020-09-01 Arizona Board Of Regents On Behalf Of Arizona State University Conditioned surfaces for in situ molecular array synthesis
US11747334B2 (en) 2016-06-20 2023-09-05 Cowper Sciences Inc. Methods for differential diagnosis of autoimmune diseases
US11774446B2 (en) 2016-06-20 2023-10-03 Cowper Sciences Inc. Methods for diagnosis and treatment of autoimmune diseases
US11371990B2 (en) 2016-11-11 2022-06-28 Cowper Sciences Inc. Methods for identifying candidate biomarkers

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EP0781465B1 (fr) 2003-11-05
CA2199510C (fr) 2001-02-20
JP3895370B2 (ja) 2007-03-22
DE69532083T2 (de) 2004-08-26
DE69532083D1 (de) 2003-12-11
CA2199510A1 (fr) 1996-03-28
US5917972A (en) 1999-06-29
JPH10505954A (ja) 1998-06-09
EP0781465A1 (fr) 1997-07-02
GB9425729D0 (en) 1995-02-22

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